gmain.c

嵌入式下基于MiniGUI的Web Browser

 * @notify: a function to call when @data is no longer in use, or %NULL.
 * 
 * Sets the callback function for a source.
 **/
void
g_source_set_callback (GSource        *source,
		       GSourceFunc     func,
		       gpointer        data,
		       GDestroyNotify  notify)
{
  GSourceCallback *new_callback;

  g_return_if_fail (source != NULL);

  new_callback = g_new (GSourceCallback, 1);

  new_callback->ref_count = 1;
  new_callback->func = func;
  new_callback->data = data;
  new_callback->notify = notify;

  g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs);
}

/**
 * g_source_set_priority:
 * @source: a #GSource
 * @priority: the new priority.
 * 
 * Sets the priority of a source. While the main loop is being
 * run, a source will be dispatched if it is ready to be dispatched and no sources 
 * at a higher (numerically smaller) priority are ready to be dispatched.
 **/
void
g_source_set_priority (GSource  *source,
		       gint      priority)
{
  GSList *tmp_list;
  GMainContext *context;
  
  g_return_if_fail (source != NULL);

  context = source->context;

  if (context)
    LOCK_CONTEXT (context);
  
  source->priority = priority;

  if (context)
    {
      source->next = NULL;
      source->prev = NULL;
      
      tmp_list = source->poll_fds;
      while (tmp_list)
	{
	  g_main_context_remove_poll_unlocked (context, tmp_list->data);
	  g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
      
	  tmp_list = tmp_list->next;
	}
      
      UNLOCK_CONTEXT (source->context);
    }
}

/**
 * g_source_get_priority:
 * @source: a #GSource
 * 
 * Gets the priority of a source.
 * 
 * Return value: the priority of the source
 **/
gint
g_source_get_priority (GSource *source)
{
  g_return_val_if_fail (source != NULL, 0);

  return source->priority;
}

/**
 * g_source_set_can_recurse:
 * @source: a #GSource
 * @can_recurse: whether recursion is allowed for this source
 * 
 * Sets whether a source can be called recursively. If @can_recurse is
 * %TRUE, then while the source is being dispatched then this source
 * will be processed normally. Otherwise, all processing of this
 * source is blocked until the dispatch function returns.
 **/
void
g_source_set_can_recurse (GSource  *source,
			  gboolean  can_recurse)
{
  GMainContext *context;
  
  g_return_if_fail (source != NULL);

  context = source->context;

  if (context)
    LOCK_CONTEXT (context);
  
  if (can_recurse)
    source->flags |= G_SOURCE_CAN_RECURSE;
  else
    source->flags &= ~G_SOURCE_CAN_RECURSE;

  if (context)
    UNLOCK_CONTEXT (context);
}

/**
 * g_source_get_can_recurse:
 * @source: a #GSource
 * 
 * Checks whether a source is allowed to be called recursively.
 * see g_source_set_can_recurse().
 * 
 * Return value: whether recursion is allowed.
 **/
gboolean
g_source_get_can_recurse (GSource  *source)
{
  g_return_val_if_fail (source != NULL, FALSE);
  
  return (source->flags & G_SOURCE_CAN_RECURSE) != 0;
}

/**
 * g_source_ref:
 * @source: a #GSource
 * 
 * Increases the reference count on a source by one.
 * 
 * Return value: @source
 **/
GSource *
g_source_ref (GSource *source)
{
  GMainContext *context;
  
  g_return_val_if_fail (source != NULL, NULL);

  context = source->context;

  if (context)
    LOCK_CONTEXT (context);

  source->ref_count++;

  if (context)
    UNLOCK_CONTEXT (context);

  return source;
}

/* g_source_unref() but possible to call within context lock
 */
static void
g_source_unref_internal (GSource      *source,
			 GMainContext *context,
			 gboolean      have_lock)
{
  gpointer old_cb_data = NULL;
  GSourceCallbackFuncs *old_cb_funcs = NULL;

  g_return_if_fail (source != NULL);
  
  if (!have_lock && context)
    LOCK_CONTEXT (context);

  source->ref_count--;
  if (source->ref_count == 0)
    {
      old_cb_data = source->callback_data;
      old_cb_funcs = source->callback_funcs;

      source->callback_data = NULL;
      source->callback_funcs = NULL;

      if (context && !SOURCE_DESTROYED (source))
	{
	  g_warning (G_STRLOC ": ref_count == 0, but source is still attached to a context!");
	  source->ref_count++;
	}
      else if (context)
	g_source_list_remove (source, context);

      if (source->source_funcs->finalize)
	source->source_funcs->finalize (source);
      
      g_slist_free (source->poll_fds);
      source->poll_fds = NULL;
      g_free (source);
    }
  
  if (!have_lock && context)
    UNLOCK_CONTEXT (context);

  if (old_cb_funcs)
    {
      if (have_lock)
	UNLOCK_CONTEXT (context);
      
      old_cb_funcs->unref (old_cb_data);

      if (have_lock)
	LOCK_CONTEXT (context);
    }
}

/**
 * g_source_unref:
 * @source: a #GSource
 * 
 * Decreases the reference count of a source by one. If the
 * resulting reference count is zero the source and associated
 * memory will be destroyed. 
 **/
void
g_source_unref (GSource *source)
{
  g_return_if_fail (source != NULL);

  g_source_unref_internal (source, source->context, FALSE);
}

/**
 * g_main_context_find_source_by_id:
 * @context: a #GMainContext (if %NULL, the default context will be used)
 * @source_id: the source ID, as returned by g_source_get_id()
 * 
 * Finds a #GSource given a pair of context and ID
 * 
 * Return value: the #GSource if found, otherwise, %NULL
 **/
GSource *
g_main_context_find_source_by_id (GMainContext *context,
				  guint         source_id)
{
  GSource *source;
  
  g_return_val_if_fail (source_id > 0, FALSE);

  if (context == NULL)
    context = g_main_context_default ();
  
  LOCK_CONTEXT (context);
  
  source = context->source_list;
  while (source)
    {
      if (!SOURCE_DESTROYED (source) &&
	  source->source_id == source_id)
	break;
      source = source->next;
    }

  UNLOCK_CONTEXT (context);

  return source;
}

/**
 * g_main_context_find_source_by_funcs_user_data:
 * @context: a #GMainContext (if %NULL, the default context will be used).
 * @funcs: the @source_funcs passed to g_source_new().
 * @user_data: the user data from the callback.
 * 
 * Finds a source with the given source functions and user data.  If
 * multiple sources exist with the same source function and user data,
 * the first one found will be returned.
 * 
 * Return value: the source, if one was found, otherwise %NULL
 **/
GSource *
g_main_context_find_source_by_funcs_user_data (GMainContext *context,
					       GSourceFuncs *funcs,
					       gpointer      user_data)
{
  GSource *source;
  
  g_return_val_if_fail (funcs != NULL, FALSE);

  if (context == NULL)
    context = g_main_context_default ();
  
  LOCK_CONTEXT (context);

  source = context->source_list;
  while (source)
    {
      if (!SOURCE_DESTROYED (source) &&
	  source->source_funcs == funcs &&
	  source->callback_funcs)
	{
	  GSourceFunc callback;
	  gpointer callback_data;

	  source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);
	  
	  if (callback_data == user_data)
	    break;
	}
      source = source->next;
    }

  UNLOCK_CONTEXT (context);

  return source;
}

/**
 * g_main_context_find_source_by_user_data:
 * @context: a #GMainContext
 * @user_data: the user_data for the callback.
 * 
 * Finds a source with the given user data for the callback.  If
 * multiple sources exist with the same user data, the first
 * one found will be returned.
 * 
 * Return value: the source, if one was found, otherwise %NULL
 **/
GSource *
g_main_context_find_source_by_user_data (GMainContext *context,
					 gpointer      user_data)
{
  GSource *source;
  
  if (context == NULL)
    context = g_main_context_default ();
  
  LOCK_CONTEXT (context);

  source = context->source_list;
  while (source)
    {
      if (!SOURCE_DESTROYED (source) &&
	  source->callback_funcs)
	{
	  GSourceFunc callback;
	  gpointer callback_data = NULL;

	  source->callback_funcs->get (source->callback_data, source, &callback, &callback_data);

	  if (callback_data == user_data)
	    break;
	}
      source = source->next;
    }

  UNLOCK_CONTEXT (context);

  return source;
}

/**
 * g_source_remove:
 * @tag: the id of the source to remove.
 * 
 * Removes the source with the given id from the default main
 * context. The id of a #GSource is given by g_source_get_id(),
 * or will be returned by the functions g_source_attach(),
 * g_idle_add(), g_idle_add_full(), g_timeout_add(),
 * g_timeout_add_full(), g_io_add_watch, and g_io_add_watch_full().
 *
 * See also g_source_destroy().
 *
 * Return value: %TRUE if the source was found and removed.
 **/
gboolean
g_source_remove (guint tag)
{
  GSource *source;
  
  g_return_val_if_fail (tag > 0, FALSE);

  source = g_main_context_find_source_by_id (NULL, tag);
  if (source)
    g_source_destroy (source);

  return source != NULL;
}

/**
 * g_source_remove_by_user_data:
 * @user_data: the user_data for the callback.
 * 
 * Removes a source from the default main loop context given the user
 * data for the callback. If multiple sources exist with the same user
 * data, only one will be destroyed.
 * 
 * Return value: %TRUE if a source was found and removed. 
 **/
gboolean
g_source_remove_by_user_data (gpointer user_data)
{
  GSource *source;
  
  source = g_main_context_find_source_by_user_data (NULL, user_data);
  if (source)
    {
      g_source_destroy (source);
      return TRUE;
    }
  else
    return FALSE;
}

/**
 * g_source_remove_by_funcs_user_data:
 * @funcs: The @source_funcs passed to g_source_new()
 * @user_data: the user data for the callback
 * 
 * Removes a source from the default main loop context given the
 * source functions and user data. If multiple sources exist with the
 * same source functions and user data, only one will be destroyed.
 * 
 * Return value: %TRUE if a source was found and removed. 
 **/
gboolean
g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
				    gpointer      user_data)
{
  GSource *source;

  g_return_val_if_fail (funcs != NULL, FALSE);

  source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data);
  if (source)
    {
      g_source_destroy (source);
      return TRUE;
    }
  else
    return FALSE;
}

/**
 * g_get_current_time:
 * @result: #GTimeVal structure in which to store current time.
 * 
 * Equivalent to the UNIX <function>gettimeofday()</function> function, but portable.
 **/
void
g_get_current_time (GTimeVal *result)
{
#ifndef G_OS_WIN32
  struct timeval r;

  g_return_if_fail (result != NULL);

  /*this is required on alpha, there the timeval structs are int's
    not longs and a cast only would fail horribly*/
  gettimeofday (&r, NULL);
  result->tv_sec = r.tv_sec;
  result->tv_usec = r.tv_usec;
#else
  /* Avoid calling time() except for the first time.
   * GetTickCount() should be pretty fast and low-level?
   * I could also use ftime() but it seems unnecessarily overheady.
   */
  static DWORD start_tick = 0;
  static time_t start_time;
  DWORD tick;

  g_return_if_fail (result != NULL);
 
  if (start_tick == 0)
    {
      start_tick = GetTickCount ();
      time (&start_time);
    }

  tick = GetTickCount ();

  result->tv_sec = (tick - start_tick) / 1000 + start_time;
  result->tv_usec = ((tick - start_tick) % 1000) * 1000;
#endif
}

/* Running the main loop */

/* HOLDS: context's lock */
static void
g_main_dispatch (GMainContext *context)
{
  guint i;

  for (i = 0; i < context->pending_dispatches->len; i++)
    {
      GSource *source = context->pending_dispatches->pdata[i];

      context->pending_dispatches->pdata[i] = NULL;
      g_assert (source);

      source->flags &= ~G_SOURCE_READY;

      if (!SOURCE_DESTROYED (source))
	{
	  gboolean was_in_call;
	  gpointer user_data = NULL;
	  GSourceFunc callback = NULL;
	  GSourceCallbackFuncs *cb_funcs;
	  gpointer cb_data;
	  gboolean need_destroy;

	  gboolean (*dispatch) (GSource *,
				GSourceFunc,
				gpointer);

	  dispatch = source->source_funcs->dispatch;
	  cb_funcs = source->callback_funcs;
	  cb_data = source->callback_data;

	  if (cb_funcs)
	    cb_funcs->ref (cb_data);
	  
	  was_in_call = source->flags & G_HOOK_FLAG_IN_CALL;
	  source->flags |= G_HOOK_FLAG_IN_CALL;

	  if (cb_funcs)
	    cb_funcs->get (cb_data, source, &callback, &user_data);

	  UNLOCK_CONTEXT (context);

	  need_destroy = ! dispatch (source,
				     callback,
				     user_data);
	  LOCK_CONTEXT (context);

	  if (cb_funcs)
	    cb_funcs->unref (cb_data);

	 if (!was_in_call)
	    source->flags &= ~G_HOOK_FLAG_IN_CALL;

	  /* Note: this depends on the fact that we can't switch
	   * sources from one main context to another
	   */
	  if (need_destroy && !SOURCE_DESTROYED (source))
	    {
	      g_assert (source->context == context);
	      g_source_destroy_internal (source, context, TRUE);
	    }
	}
      
      SOURCE_UNREF (source, context);
    }

  g_ptr_array_set_size (context->pending_dispatches, 0);
}

/* Holds context's lock */